2006 - Dynamics AX 4.0 - March: The seventh major Axapta release brought with it an updated look and feel. As the first version that Microsoft was involved in from the beginning it attempted to integrate better with existing Microsoft technologies.

AOS became a true Windows service

.Net business connector was provided

CLR Interoperability was introduced

XML data exchanges were supported through a set of code classes (Application Integration Framework)

Full Unicode support was introduced

Service Management module.

2008 - Dynamics AX 2009 - June: Originally named AX 4.1, later renamed to AX 5.0 (and finally AX 2009), the eighth major release of Axapta brings with it yet more improvements to the UI. This new version adds role-based concepts to both the Enterprise Portal and windows clients, support for timezones (utc), a new Site inventory dimension, and Enterprise Portal development through Visual Studio projects.

2011 - Dynamics AX 2011 - Q1: Sometimes dubbed AX 6, it is said to include additional improvements to the user interface and application enhancements focused on specific industries like Retail, Media & Entertainment, and Public sector. Originally AX 2011 was due to be released toward the middle of 2010, but this has since been put back to Q1 2011.